<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>lesson 18</title>
  <script src="https://unpkg.com/vue@next"></script>
</head>

<body>
  <div id="root"></div>
</body>
<script>
  const app = Vue.createApp({
    data() {
      return {
        count: 1
      }
    },
    methods: {
      handleAddOne() {
        this.count += 1
      }
    },
    template: `<Counter :count="count" @add-one="handleAddOne"/>`
  })
  app.component('Counter', {
    props: ['count'],
    // emits: ['addOne'], //方便我们找到自定义事件
    methods: {
      handleClick() {
        this.$emit('addOne')
      }
    },
    template: `<div @click="handleClick">{{count}}</div>`
  })
  const vm = app.mount('#root');
</script>

</html>